Paenungulata
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Scientific name | ||||||||||||
Paenungulata | ||||||||||||
Simpson , 1945 | ||||||||||||
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The paenungulata provide a taxon of mammals is where the three orders of mammoths , of manatees and hyraxes are summarized. Extinct representatives are among others the Embrithopoda and the Desmostylia .
features
Genetic studies have largely confirmed that this group belongs together, but there are only a few morphological features. This includes details in the structure of the ankle bone , that there are 19 or more thoracic vertebrae and that the third molar is significantly larger than the second in both the upper and lower jaw.
Tribal history
The first scanty finds are known from the Paleocene and were found in Morocco. These include Eritherium , the oldest known representative of the proboscis animals, and Ocepeia , a primitive member of the Afrotheria, who is associated with the Paenungulata due to the structure of the teeth. The group is certainly of older origin and is likely to have originated as early as the Cretaceous period . The group had its first heyday in the late Eocene and Oligocene , there were numerous families of hyrax and proboscis, mainly in Africa . The marine manatees and the proboscis later achieved almost worldwide distribution. Not least due to human intervention, there are only around eleven species of this group today.
Systematics
The name Paenungulata ("near ungulates") indicates that this group was previously thought to be representatives or at least close relatives of the " ungulates ", a group composed according to morphological criteria, with the hyraxes being considered relatives of the unguided ungulates for a long time . Due to genetic studies, however, there is largely no doubt that the Paenungulata belong to the diverse group of Afrotheria and are therefore neither related to the ungulate nor to the unpaired ungulates.
Within the Paenungulata, manatees and proboscis make up the taxon of Tethytheria , which is the sister taxon of the hyrax. This is expressed in the following cladogram according to Emmanuel Gheerbrant and research colleagues 2014:
Paenungulata |
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In addition to the three recent orders, the Paenungulata also include the Embrithopoda (whose most famous representative is Arsinoitherium ) and the Desmostylia (a group of large, aquatic animals known from the North Pacific).
literature
- TS Kemp: The Origin & Evolution of Mammals. Oxford University Press, Oxford 2005. ISBN 0198507615
Individual evidence
- ↑ Emmanuel Gheerbrant: Paleocene emergence of elephant relatives and the rapid radiation of African ungulates. PNAS. 106 (6), 2009, pp. 10717-10721
- ↑ a b Emmanuel Gheerbrant, Mbarek Amaghzaz, Baadi Bouya, Florent Goussard and Charlène Letenneur: Ocepeia (Middle Paleocene of Morocco): The Oldest Skull of an Afrotherian Mammal. PLOSone 9 (1), 2014, p. E89739 ( [1] )